Science Friday - (Part 1) Endangered Species Act at 50: Hawaiian Land Snails

Episode Date: January 8, 2024

On December 28, 2023, the Endangered Species Act (ESA) turned 50 years old. It was enacted in 1973 with almost unanimous support in Congress, with a goal to save plants and animals from extinction. It’s considered one of the most important environmental policies in US history, and it transformed conservation. It may have even helped save one of your favorite critters, like humpback whales, bald eagles, manatees, and grizzly bears.To mark the ESA’s 50th birthday, we’re looking at how it works, how successful it’s been, and what its future may look like. Ira starts off by talking with Dr. Judy Che-Castaldo, biologist for the US Fish and Wildlife Service’s Branch of Species Status Assessment Science Support.Then, we head to the extinction capital of the world: Hawai‘i. Kāhuli, also known as Hawaiian land snails, live all over the Hawaiian islands. At one point, around 750 species existed, but more than half have gone extinct. Ira talks with two conservationists dedicated to saving the snails: Dr. David Sischo, coordinator of the Hawai‘i Snail Extinction Prevention Program, and Keahi Bustamente, Maui Nui field coordinator for the program.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Just before the new year, the Endangered Species Act turned 50 years old. The Act has actually been very successful. 99% of the listed species have been prevented from growing extinct. It's Monday, January 8th, but it's also Science Friday. I'm John Dankowski. In 1973, Congress passed the Endangered Species Act to save plants and animals from the brink of extinction. It's been revered as one of the most important environmental policies in U.S. history. And it might have even helped to save some of your favorite critters, like humpback whales, bald eagles, manatees, grizzly bears, or even Hawaiian land snails.

So we're going to look back today at 50 years of the ESA. Here's Ira Flato. Joining me is Dr. Judy Chi Castaldo, biologist for the U.S. Fish and Wildlife Services Branch of Species Status Assessment Science Support. Joining me from Madison, Wisconsin, and she's not speaking as a spokesperson for the U.S. Fish and Wildlife Service. Welcome to Science Friday. Thanks for having me. Let's talk about how critical the Endangered Species Act is to Conservation. What does it allow scientists to do? Well, I mean, the stated purpose of the Act is to provide a means to conserve, threaten, and endangered species, as well as the ecosystems upon which they depend. So that's a really clear and powerful statement, and that is what it allows us to do. So it's actually made a law, right,

out of conserving species? Yes. And how many species are actually listed on it at the present time? So that number changes all the time. Currently, it's over 2,300. Over 2,300? Yeah. If it gets longer, I would suppose that's a bad thing. Not necessarily. That means more species are protected. It just fluctuates over time, you know, for many, many different reasons. Sometimes species change. They're no longer considered as species or some species may be split into multiple species, you know, so for many various reasons, that number fluctuates a lot. And is it considered a very successful act? Yes. So there are multiple ways to measure the success of the act. And depending on how you measure it, the answer is going to be different, right?

So one of the goals of the act is to recover the listed species to the point where they no longer need the protections of the act and can be delisted. And in that sense, relatively few species have been delisted due to recovery. On the other hand, another goal of the act is also to avoid extinctions. And in that sense, the act has actually been very successful because very few listed species have gone extinct. Wow, that is?

Yes. So actually 99% of the listed species have been prevented from growing extinct. 99%. Yeah, pretty good. Yeah. Let's get it to some of the machinations, some of the weeds about the act. Let's say I have an imaginary three-headed frog, and I think it deserves federal protections. All right, give me the process involved of getting that frog listed.

anybody can petition for a species to be listed. And so once a species is petition, the services, they have to consider that species, see whether they are warranted for the protections of the act. That's the first step. And is that part of your job in analyzing that info? Yes, exactly. So I do the part where once it passes the petition process, there's a 90-day finding where we say that, yes, there does seem to be enough information that suggests that the species may warrant lifting, and then it gets into the full consideration.

Now, let's move forward and see what happens, because once my three-headed frog is listed, what kinds of protections does it get? The act is actually pretty unique in that it also requires people to work actively to recover threatened and endangered species. So when a species is listed, there are generally two. types of actions that are triggered, protective measures and recovery actions. So for protective measures, that mainly includes prohibiting take and what are called interagency consultations. So take is basically hurting or attempting to hurt a species in any way. And so that's prohibited

and that's pretty straightforward. For interagency consultations, so, all federal agencies are required by the Act to help conserve the listed species. And so any time that an agency proposes to do a project that may affect a listed species, anything like putting up a dam, they have to consult with the managing agency. And does somebody have to keep track of them once they're on the list? Yes. Oh, for sure, yes. So we have those protective measures, which are that prohibitive take and in an emergency consultations, but then the other type of actions is recovery actions. And that means coming up with a plan for actually how to bring back the species to a recovered

state, defining what that recover state looks like for each species, because that will look different. Also designating critical habitat and firmly checking on the species every five years or so to see if it's improving or not. So let's look ahead for the next 50 years. What would be a successful 50 years from now? I'm imagining that there will still be a lot of work to do in 50 years, even if we are very successful in the next few years, if that makes sense.

Have you analyzed at all how climate change might speed up the loss of species? Oh, yeah. I mean, not me personally, but a lot of research is out there, right, about how climate change is accelerating the rates of species loss and biodiversity loss around the world. Yeah, I think that will definitely impact the workload of evaluating which species warrant protections. Yeah, that's part of that whole 50 years from now, isn't it? Oh, yes. Yeah, and beyond for sure. Yeah. Well, thank you very much for enlightening us today.

Yeah, thank you so much for having me. This is great. Dr. Judy Chi Castaldo, biologist for the U.S. Fish and Wildlife Services Branch of Species Status Assessment Science Support. She was joining us from Madison, Wisconsin. Continuing our conversation on the 50th anniversary of the Endangered Species Act, we're headed to the extinction capital of the world. Hawaii, did you know that? To meet Kahuli, also called Hawaiian land snails. These snails have beautiful stripy cone-shaped shells, and they come in an array of colors.

There used to be around 750 species of cahouli scattered around the Hawaiian Islands, but more than half have gone extinct. So what's it going to take to save the snails? Let's find out. Joining me are Dr. David Sisko, coordinator of Hawaii's snail extinction prevention program based in Honolulu, Hawaii. and Kiahi Bustamante, Maui Nui Field Coordinator for the program based in Maui Hawaii. Welcome to Science Friday. Aloha, Ira. Honored to be here. Aloha, Ira.

Let me start with you, David. Why is Hawaii the extinction capital of the world? That's a great question. And Hawaii is one of the most isolated land masses on Earth. And so a lot of the animals that made it out here evolved without a lot of the pathogens and other animals that are usually on continental landmasses like mammals and reptiles. And so what made it out here evolved unique niches. And, you know, when introduced species got here, which we have very many of them, the animals here are just not well adapted to the kinds of predators that are now here.

And so how dire then is the situation with Kahuli? It's bad. The Hawaiian Islands had over 750 species, just to give you an idea that that's the same number of species that exists. in the continental North America. And Hawaii is one 1,700th land area of North America. And so we had just this incredible diversity here. About half of that is gone already. And we're on the verge of losing another 100 species this decade without significant conservation intervention.

Wow, that really is something. Kiyahe, is that because of environmental factors? or do people love the shells and collect them? What's the reason for this? You know, it's mostly to do with environmental factors, but at one time it was a trend to go into the mountains and collect snails, kind of like collecting baseball cards. Really?

Yeah. Describe the snail for me. I'd like to know why they were so interesting. Oh, man. The most incredible colors and shapes you've ever seen. It's common for people to see, sea shells, I think, and be just blown away by their beauty. But these snails are on land and have just the same amount of beauty and elegance to their

shells. So for that very reason, it became, you know, a popular pastime. And something that the native people really, really revered. And we embodied them with our gods. They were known to be body forms of demigods. They were kind of like the royalty of the forest. Wow. That's the kind of reverence that we had for them.

And that's one of the reasons why I would imagine it's so awful to hear that they're disappearing. It is. It's really sad. And it's heartbreaking for a native person who has been able to experience. experience them, you know, they are so rare and very, very few Native people have been able to experience them or even know that they exist and that they're going extinct. Wow. Now that I've heard this, I'm really interested in your strategies to save them. Fill me in on that. It's Emergency 911. These things are going extinct really fast.

And so most of what we're doing is trying to intervene in extinction and stabilize populations. And so that includes a large captive rearing program. So we collectively between our laboratory and other partner laboratories that are also rearing snails, we have over 60 species in captivity. Many of them no longer have wild counterparts, so they're extinct in the wild. And so we're getting them into the lab. We're getting their numbers up. And then we're building these protected areas.

And we're getting them back out onto the landscape. But honestly, like our efforts for the next decade will be to just try and keep these animals on Earth. How easy are they to breed? You have to go out and find them, bring them back to the lab and breed them. Kiahi, how easy is that? Oh, it is not easy, Ira. Really difficult. Most of them are in really, really remote areas at the top of our mountains.

Really rugged terrain. A lot of times we need to access these areas. with helicopters and stay there for a week at a time camping in the rainforests and pushing through miles of dense vegetation across ravines and gulches and streams. Yeah, it is not easy to find these things. And probably one of the most difficult, really needle in the haystack kind of work. And so once you get them into your little lab. laboratory habitat, how easy is it to breed them? Many of the species we're working with have really bizarre life histories.

So they can live close to 20 years. They take five years to reach maturity. And once they're mature, they usually only give birth to one to seven offspring per year. So that's much different than a common garden snail, which can lay thousands of eggs over its short life span. So many of the snails are like dealing with a long-lived bird or mammal. And the laboratory is, it's kind of like an emergency room. You walk in and all the animals are in environmental chambers, which are mimicking the conditions in the wild, which are usually upper elevation areas that are cooler and more humid.

So it really feels like an ER. And, you know, it's a decades-long commitment to getting these animals through to a point. where we could put them back into the wild. That's amazing. So I'd ask then, given all these difficulties, how well are your strategies working here for saving them and getting them back in the wild? Well, our strategies are working really well for the species that we're bringing in for the most part. The problem is the logistics of scaling up.

I mean, we've got 100 species across five islands that are going extinct, and we're a really small team. And it's not just happening in one area on one island on one forest reserve. It's across private and public lands. We have the tools and the techniques to do what we need to do, but it's the capacity issue. That's the problem. So you're not really trying to get the snails off the endangered species list. You just, you want to just keep them around, right?

Yeah, we're trying to keep them on Earth at this point. and I don't think that they will be recovered in my lifetime for sure. I think this will be like a multi-generational tag team effort. We've been talking about 50 years of the Endangered Species Act. How does the Act affect your work? There are 44 species listed on the U.S. Endangered Species Act, 44 species of snail. About 13 or 14 of those are still extants or still around. There's many species that are not listed that are extinct in the wild or will be very, very soon that are not even listed.

But the U.S. Endangered Species Act has been crucial for snail conservation. You know, many of the species we have in captivity are around because of the funding that we receive from the U.S. Fish and Wildlife Service. And part of that comes from the U.S. Endangered Species Act. And so without the funding, we couldn't do what we do. Now, I know that the governor of Hawaii proclaimed last year, 2023, as the year of Kahuli, what was that like, Kiahi? How did that affect things and people?

Well, it definitely brought more attention just to the public. People were exposed to the snails that maybe wouldn't have without it being the year the Kahuli. It also brought some recognition to some of the endemic. snails on each island where people were able to vote for the snail that they wanted to be representing their island. So now there's a state snail for each island. So I was really pleased to be around for something like that and hopefully we'll see more years of the Kahuli to come. Well, I want to thank you for both of you for what you're doing and thank you for taking time to be

with us today. And good luck to you in the future. Thank you, Ira. Thank you, Ira. Dr. David Sisko, coordinator of the Hawaii's snail extinction prevention program based in Honolulu, and Kiahi Bustamente, Maui-Nui Field Coordinator for the program based in Maui Hawaii. To see photos of these beautiful snails, and I mean, they are really gorgeous, visit sciencefriiday.com slash endangered. Coming up on our next episode, we're going to continue our conversation about the Endangered Species Act, and we'll talk with scientists who are trying to save at-risk orchids and also one of the most endangered species in the country, the Red Wolf. Thanks so much for joining us. I'm John Dankoski. Talk to you soon.